In communications networks, such as LTE networks, network components are often tested using devices that generate test packets, send the packets to a device under test, receive responsive packets from the device under test, and generate statistics indicative of the performance of the device under test. For example, in LTE networks, it may be desirable to test the functionality of a serving gateway (SGW) by sending streams of test packets to the SGW. In some tests, the streams of test packets mimic the traffic that would be received by such a node if the node were operating in a live network. In other tests, the goal is to send streams of packets that test the extremes of the operational capabilities or stress test the device under test.
Testing the functionality of a network component, such as an SGW, involves formulating packets that include various protocol layers. Two types of protocol packets that are received by an SGW are RTP packets and GTP encapsulated RTP packets. RTP packets carry or transport media data for real-time applications, such as audio, video, or voice over IP applications. In LTE networks, the GTP protocol is used to tunnel user plane and signaling packets between tunnel endpoints. For example, one tunnel endpoint can be an eNode B, and the other tunnel endpoint can be a serving gateway, GTP packets each include a GTP header that identifies the tunnel endpoints. When one of the tunnel endpoints changes, the GTP header changes. For example, when a user element (UE) moves from one radio tower to another, the originating IP address for the tower changes. Another example of when the GTP header changes is when traffic starts using a different bearer channel from a current bearer channel. Such a switch can occur when a dedicated bearer is established, is deleted, and the traffic continues to be transmitted over a default bearer. The terminal endpoint identifier (TEID) in the GTP header changes when the switch from the dedicated bearer to the default bearer occurs.
It is desirable for equipment that generates simulated GTP packets to be able to efficiently generate the packets and also to efficiently update the generation of the packets when an IP address or other aspect of a GTP header changes for a given stream.
Accordingly, there exists a need for methods, systems, and computer readable media for generating GTP encapsulated RTP packets in an LTE node simulator.